Door



Sept. 1, 1925.

H. BACKMAN ET AL DOOR 3 Sheets-Sheet 1 Filed April 24 1922 Sept. 1, 1925.

H. :BACKMAN ET, AL

noon Filed April 24, 1922 3 Sheets-Sheet 5 (in 072% EacKma/w *fiw JWL Patented Sept. iv

7 UNITED: STA Tssf 1,551,780 PATENT. OFFICE.

HERMAN BAoKMAN ANnEnwARn nnnoxnnnnd, or CHICAGO, InnINoIsnssreNons I TO VARIETY FIRE noon COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or A ILLINoIs.

DOOR.

Application filed April 24, 1922. Serial No. 55 ,344..

To all whom it may concern:

Be it known that we, HERMAN BACKMAN and EowARD L. B CKERLEG, citizens of the United States, residing in Chicago, in the county of Cook and 'State' of Illinois, have invented a certain new it and useful Improvement in Doors,*of which the following is-a flull, clear, concise, and exactdescripi tion, referencebeing' had to the accompanying drawings, forming apart of this specification.

This invention relates .to doors I and though capable of a Wide and varied range of uses, is particularly adapted for use as a fire door for elevator shafts and the like. 7 One object-of this invention is to provide an improved collapsible door of the sliding type so constructed as torequire a minimum operating space and so controlled as to, render the operation ingly simpleand easy; i

Another ob'ect is to provide a'novel means for suspending and controlling the several door sections so that when the door is extended it. will completely cover the door opening and when contracted the several sections. will automatically assume a super- {imposed relation in planes parallel to the "door opening.

' Other objects and advantages will hereinafter appear.

* One: embodiment of the invention is illustrated in the accompanyingdrawings.

The views of he drawingsare as follows;

Figure 1 is affront elevation ofa door constructed in accordance with the present invention; p I.

Figure2 is'a vertical section through the door taken substantially on the line 2-2 of Figure/'1'} Figure 3 is a fragmentary horizontal section'through one edge of the door and illustrating the guides therefor; Figure 4 is a vertical, longitudinal section through the doorsupporting a drum on a somewhat larger scale; 1

Figure 5 is a fragmentary, horizontal, longitudinal section through one'end of the drum on a still larger scale; v q

Figure 6 is a vertical transverse section taken on the line 66 of Figure 5; 4

Figure 7 is a vertical section taken onthe line 7 7 of Figure-4; and drawn to the same male as'Figuresfi and 6, a

thereof exceed 1 the lower door section. I

ably ofh-eavy sheet metal and each preferably provided with upstanding vertical flanges 14: and horizontal flanges 15. The sections are mounted for vertical sliding movement in parallel planes from their respective closing position to position above the cloorway.- For this purpose suitable guides 16 and 17 are secured adjacent the opposite sides of the doorway. Each guide 'is provided with an inner channel 18 for receiving a vertical. shoe 19 secured to a vertical flange 14' of the upper door section and an outer channel 20 for receiving a vertical shoe 21 secured to a vertical flange'14 of The doorseotions 'aresupported and con= trolled in such manner'that as one section is moved from its closing position to a position above the doorway the other section is automatically moved in asimilar manner so that in the withdrawn position of the door the sections assume ZL'SUPGYlHlPOSQd relation.

In thepresent instance the door 18 made up of two substantially flat rectangular sections 12 and 13 each formed prefer- Various means may be employed for this purpose. In the present instance however,

th lower door section is supported by means of a cable 23 preferably fixed as at 22to the horizontal flange 15, thereof and passing over apulley 9A and through thewall 10 to a rotatable drum 25. mounted in a suitable bracket 26 secured to The pulley is the wall. The upper door section is supported by means of a cable 2'? fiXe-dat one end to a pin 28 secured to thebracket 26. Cable 27 is threaded beneath a pulley 29 mounted in a bracket 8O carried by the up -per door section, over a pulley 31 mounted in th bracket 26, and

through the wall to the'drum 25. r

The drum is preferably hollow as shown in Figure 4: and is mounted between a pair of'brackets 3233 secured to the outer side of the wall.- One end of the drum'is supported by means of a shaft'84'fixed against rotation in the bracket 32. Shaft 34 projects through a pair of spaced bearings 35 and 36, the former secured within one end of the drum and the latter secured intermediate the ends thereof. The other end of the drum is preferably supported by a stub shaft 37 extending from a sleeve 38 fixed within that end of the drum and journaled in the other bracket 33. A coil spring 39 surrounding the shaft 34 tends at all times to rotate the drum in a clockwise direction (Figure 2). One end of the spring projects through the bearing 35 and is secured within a groove 40 in the hub portion thereof by any convenient means such as a screw 41. The other end of the spring is secured to the fixed shaft 34. For this purpose a sleeve 42- is secured to the shaft and the end of the spring is firmly clamped within a groove 6L3 thereof by means of a plate 44.

The upper free end of each of the cables 23 and 27 are secured to the winding portion or reel 45 of the drum. The reel is preferably spirally grooved to receive the cables and is preferably conical in form so that a uniform tension is maintained in the cables as the tension in the spring varies with the winding and unwinding operations. The tension in the spring is su'tficient to raise the upper door section from its closing position to its position above the doorway but the rotation of the drum and hence the movement of the upper section is controlled by the movement of the lower section.

Although the spring may be placed under such tension as to raise both door sections when the door is released it 'is preferably so tensioned as to merely counterbalance the combined weight of both sections. lVhen relieved of the weight of the lower door section however, by a manual raising of that section, the spring acts to raise the upper section.

The door may be provided with a latch of any appropriate construction for retaining the door in closed condition. The latch illustrated in Figure 1 is of a well known type and comprises a rotatable disc 46 conveniently mounted on the lower door section and controllin the position of the latch bolts 47 and 48. The inner ends of the latch bolts are pivotally connected with the disc at points 49 and 50, respectively, above and below the axis of the disc. The bolts extend laterally in opposite directions through suitable openings in the opposite vertical flanges 14 of the door section and are engageable beneath the fixed cam members 51 and 52 preferably secured to the front faces of the guides 16 and 17, respectively. A tension spring 53 secured at one end to the disc and at the other end to the door section, tends to rotate the disc in a counter-clockwise direction (Figure 1) to yieldably maintain the bolts in extended or latching position. The disc may be rotated in the opposite direction to withdraw the bolts by means of a handle 54 secured to the disc.

To raise the door to open position it is only necessary to pull upwardly on the handle 54. This will cause a rotation of the disc 46 in a clockwise direction (Figure 1) to withdraw the latch bolts 47 and 48. By a continued pull upwardly the lower door section is raised to its withdrawn position above the doorway. This manual raising of the lower door section permits the spring 39 to rotate the drum 25 so as to effect an upward movement of the upper door section. In view of the cable and pulley connection between this section and the drum the upper section moves upwardly only half as fast as the lower section so that both sections reach their uppermost positions above the doorway at substantially the same time. To close the door it is only necessary to push downwardly on the lower section. As this section moves toward closing position it causes a rotation of the drum in the opposite direction against the influence of the spring 39, thus permitting the upper section to move downwardly by gravity.

Numerous changes may be made in the embodiment of the invention hereinabove described without departing from or sacrificing any of the advantages of the invention defined in the following claims.

o claim:

1. In combination, a pair of closure sections one superposed above the other in closed position and both movable in the same direction to open position, a drum provided with counter-balancing means therefor, a spiral pulley mounted upon said drum, and a flexible element having one end attached to the lower closure section and its opposite end fixed, said flexible element having looped connection with the upper closure section and wrapped on the spiral pulley between its ends.

2. In combination, a pair of closure sections one superposed above the other in closed position and both movable in the same direction to open position, counter-balancing means for said sections and a single flexible element having one end attached to the lower closure section and its opposite end fixed, and a pulley having looped connection with the upper closure section and coopcrating loosely with said counter-balancing means between its ends.

3. The combination with a wall having a doorway of a pair of closure sections one superposed above the other in closed position and both movable in the same direction to open position, a winding element, and a flexible element attached at one end to the lower closure section substantially centrally between its opposite sides and fixed atits opposite end, said flexible element having looped connection with the upper section substantially centrally between its opposite sides and wrapped upon the winding element between itsends; o

4. The combination with a wall having a doorway of a pair of closure sections one superposed above the other in closed position and both movable in the same direction to open position on one side of the wall, a drum mounted on the other side of the wall above the doorway, and a flexible element attached at one end to the lower closure section substantially centrally between its opposite sides and fixed at its opposite end, said flexible element having looped connection with the upper section substantially centrally between its opposite sides and wrapped upon the drum between its ends.

5. The combination with a doorway of a pair of closure sections for said doorway, a winding element, and a single flexible element cooperating with said winding element and having connection with said closure sec? tions substantially centrally between their opposite sides, said winding element effecting differential movementof the sections in operation without obstructing the doorway. 6. The combination with a pair of closure sections one superposed above the other in closed position and both movable in the same direction to open position of means for effecting a differential movement of said sections in operation and' means in operative relation with said first means for setting up a counter-balancing action to the differential movementof said sections varying withthe varying vertical positions of the sections to counter-balance the sections throughout their movement. I

In witness whereof we hereunto subscribe our names this 21st day of April, 1922.

HERMAN BACKMAN. EDVVARDL. BECKERLEG. 

